Is Deuteronomy 13 totalitarian? In totalitarian states loyalty to the party is everything. Family members get recruited to spy on other family members. Any deviation from the party line is reported. Those deviating are labeled as reactionaries or enemies of the people. They are eliminated or sent to camps.
Deuteronomy 13 says that you must eliminate first prophets who encourage rebellion against the Lord, then your brother, son, daughter, wife, or best friend if they try to entice you away from God, and finally whole cities if they turn to other gods.
This is not liberal toleration or multiculturalism.
In Reading Deuteronomy, Stephen Cook says this is either/or thinking and that it is most applicable to eschatological thought where the triumph of God at the end of history is contemplated. Then there will be community solidarity and all that is anti-God will be eliminated. He says Deuteronomy 13 compares to sayings of Jesus like the one in Luke 14:26 about discipleship requiring you to hate father, mother, wife and children. Yet he says that the Bible in many ways acknowledges that you cannot apply either/or thinking in real life.
He emphasizes how 13:14 requires inquiry, search, and questioning before one can take action. Some semblance of due process has to happen. Thus the text recognized the possibility of false accusations and hasty judgment. He points out that the kind of action against prophets urged in 13:1-5 was attempted against Jeremiah (Jeremiah 20:10 and 26:8). The point of that is that Jeremiah seems to have been in the circle of Deuteronomy so the book was not compiled in ignorance of the possible abuse of chapter 13.
As a Christian, I also thought of the actions taken against Jesus (and Stephen) as showing the dangers of any attempt to enforce Deuteronomy 13 in real life.
To Cook this passage speaks of the radical requirement to keep the first commandment. You have to brush aside the fulfillment of this as eschatological rather than of this age in order to use this passage as a weapon.
To be frank, I do not find anything justifying an eschatological interpretation of the chapter in the text. You have to turn to a kind of canonical context in order to make this interpretation. In other words, in the context of the later prophets and even the New Testament you can take these words up as a kind of projection of the ultimate triumph of God.
Cook rightly shows that Deuteronomy 13 depends upon the language of Near Eastern vassal treaties. He thinks this chapter and chapter 28 depend on Assyrian treaty language. The vassal treaty of Esarhaddon from 7th century Assyria talks about conspiracies of prophets and close relatives just as does Deuteronomy 13.
There is a discussion among scholars about whether late Bronze Age Hittite vassal treaties might not be an even better match for Deuteronomy 13. Joshua Berman has argued that Deuteronomy 13 may rely on the Hittite treaties and so be much older than the 7th century. There have been scholarly responses to Berman. See here. Cook doesn’t mention the Hittite treaties. He obviously disagrees with Berman.
I wonder if there is a middle ground. Berman’s thesis is suspect because certain kinds of apologists will use it to push for Moses as literal author. This seems to me to be a non-starter for several reasons. However, the gist of Deuteronomy 13 could be very old. I say this partly because the role of the Levites as enforcers of something like Deuteronomy 13 seems to be very old. Also there are stories in Judges about the tribes taking collective action against a single tribe that seem to follow a pattern similar to Deuteronomy 13:12ff.
The provisions of the Hittite and Assyrian treaties were meant to enforce political loyalty. Deuteronomy 13 apparently adapts them to enforce a theological loyalty.
As far as the ethics of this are concerned it seems to me that as usual Cook has made some good points that mitigate a practice that is clearly culturally alien to me. Yet I have a suspicion that this law was enforced in real life more often than we would like to think.